Screening of passengers at the airport security check point is one of the most critical measures to ensure our nation’s aviation security and safety. In this study, we investigate the operational efficiency and inspection effectiveness of passenger screening, including the magnetometer (MAG), X-Ray machines, manual wand search, trace of explosive residuals, and private screening at an airport. Passenger volumes by the day of the week and times of the day, along with the corresponding staffing levels of the screening personnel are modeled. Performance of the security system with respect to passengers making the flights on time is evaluated for various staffing and resource levels. Passenger data collected from a U.S. airport are used to demonstrate the benefits of the simulation.